The vehicle door lock device of this type is disclosed in, for example, Patent Document 1 or 2 below. In the vehicle door lock device described in Patent Document 1 or 2 below, the electric actuator includes: an active lever, which is rotatably assembled to the housing, and is capable of switching the open link between the unlocked position and the locked position; a gear unit arranged on an outer side of the active lever; an electric motor for rotationally driving the gear unit; and a converting mechanism provided between the active lever and the gear unit, for converting motion of the gear unit into motion of the active lever, and the gear unit includes: a worm, which is rotationally driven by the electric motor; and a worm wheel, which is rotatably assembled to the housing to mesh with the worm, and is linked to the active lever through the intermediation of the converting mechanism.